The performance evaluation of a urine malaria test (UMT) kit for the diagnosis of malaria in individuals with fever in south-east Nigeria: cross-sectional analytical study

Abstract

Doc number: 403

Abstract

Background: Accurate rapid diagnosis is one of the important steps in the effort to reduce morbidity and mortality of malaria. Blood-specific malaria rapid diagnostic tests (RDTs) are currently in use but other body fluid specific diagnostic test kits are being developed. The aim of the present study was to evaluate the performance characteristics of a one-step Urine Malaria Test(TM) (UMT) dipstick in detecting Plasmodium falciparum HRP2, a poly-histidine antigen in urine of febrile patients for malaria diagnosis.

Methods: This was an observational study in which a urine-based malaria test kit was used in malaria diagnosis in a normal field setting. Two hundred and three individuals who presented with fever (≥37.5°C) at seven outpatient clinics in Enugu State during periods of high and low transmission seasons in Southeastern Nigeria were enrolled. Matched samples of urine and blood of consecutively enrolled subjects were tested with UMT and blood smear microscopy.

Results: With the blood smear microscopy as standard, the disease prevalence was 41.2% and sensitivity for the UMT was 83.75% (CI: 73.81 to 91.95%, Kappa 0.665, p =0.001). The UMT had an LLD of 120 parasites/μl but the sensitivity at parasite density less than ≤200 parasites/μl was 50% and 89.71% at density ≥201 parasites/μl with specificity of 83.48%. The positive and negative predictive values were 77.91% and 88.07%, respectively.

Conclusion: The UMT showed moderate level of sensitivity compared with blood smear microscopy. The test kit requires further improvement on its sensitivity in order to be deployable for field use in malaria endemic regions.